John b



(No Model.)

J. E. JERROLD.

JOINT OR SEAM FOR STEAM BOILERS.

Patented Oct. 27, 1885.

I, ill/ N. PETERS, PhohrLithngrzphur. W-ahingfon. D. c

UNiTEn STATES PATENT OFFICE.

JOHN E. JERROLD, OF MILWAUKEE, IVIS, ASSIGNOR OF ONE-HALF TO W'ILLIAM R.EDIVARDS AND ABRAHAM B. BLACK, OF SAME PLACE.

JOINT OR SEAM FOR STEAM-BOILERS.

SPECIFICATION forming part of Letters Patent No. $29,314:, dated October27, 1885.

Serial No. 1'73 538. (No model.)

To all whom it may concern.-

Be it known that 1, JOHN E. JERROLD, a citizen of the United States,residing at Milwaukee, in the county of Milwaukee and State 5 of\Visconsin, have invented certain new and useful Improvements in Jointsor Seams for Steam-Boilers; and I do hereby declare that the followingis a full, clear. and exact description of the invention, which willenable others skilled in the art to which it appertains to make and usethe same.

My invention relates to seams for steamboilers and the like, the objectbeing to provide a seam which, while inexpensive and [5 simple, will beextremely strong and durable.

Heretofore in the manufacture of steamboilers an ordinary straight seamhas been employed; but such seam has been found to be objectionable,fromthe fact that in calking the seam to make it tight furrows are made inthe iron,which materially weaken the boiler at the joint or seam.Attempts have been made to strengthen the straight seam by in troducingwelts on the inside; but this has 2 been found objectionable,inasmuch asa clumsy seam orjoint is the result of the welts, and in addition tothis it is quite expensive.

With the above and other objects in View the inventionconsists,primarily,in providing 0 a joint or seam formed by curving themeeting or lapping edges of the boiler and securing them together.

In the drawings, Figure 1 is a plan View of asufficient portion of aboiler to illustrate my invention. Fig. 2 is a section of the same.

Corresponding parts in both the figures are denoted by the same lettersof reference.

Referring to the drawings, A A represent two sections of an ordinarysteam-boiler, the

edges of which are provided or formed with curves a. These edges arelapped sufficiently to entirelyand effectually close the seam or joint,and the curved edge of each section is secured to the other section by aseries of bolts or rivets, b, which are arranged to describe an arc of acircle equal to that of the meeting edges of the sections. In additionto this fastening, a series of rivets, c, are provided,with the space (1between the lapping edges of the boiler.

By the above construction it will be seen that increased space isafforded for the rivets or securing means. It will be observed that asthe seam or joint is curved increased space or area is provided for thecalking-tool, and the strain is divided on a larger area. Anotherdecided advantage of my improvement is that the caiking will be moresolid on the curved seam, as the calking-tool is at all times pointingtoward the center. Further than this, the joint before described is muchmore durable than the joint where wells are employed, and is much lessexpensive.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is-

A boiler having its edges curved outwardly from end to end and lapped,and securing meanssuch as bolts or rivets-securing the lapping edgestogether, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

JOHN E. JERROLD.

\Vitnesses:

JOHN H. TRIMBLE, A. O. HENRY.

